Ottó N Thorláksson’s black redfish

Last week staff at HB Grandi’s production plant in Nordurgardur, Reykjavík noticed something unusual, a black redfish that had been landed as part of Ottó N Thorláksson’s catch.

We contacted Kristján Kristinsson, a fisheries scientist at the Marine Research Institute, and one of its leading redfish specialists. Kristján said that he had not seen a black redfish before, but after discussing it with another of the Institute’s specialists, Jónbjörn Pálsson, their conclusion was that this was a pigment aberration and while it’s rare, it is not unknown.

‘We have seen redfish like this before, although this is the darkest one that we have seen. We found a reference to this in a text Jónbjörn wrote in 2013, which says; The colours of a fish is determined by coloured skin cells. These cells are special cells that contain pigments and reflect light. The cells contain particular elements that carry pigment and these can expand or contract within the colour cells. As they contract the colour fades and the strength of the colour is determined by how much expansion there is. There are variations between species as to how active these cells are. Golden redfish tends to be always the same colour while cod can be much more changeable.”

“There are occasional instances of fish with highly different pigments. These are thought to be due to genetic imperfections that mean the colour cells are either the wrong colour or are missing. The redfish I have seen with colour aberrations have been either grey or two-coloured, they tend to have dark grey upper parts and a red belly. These two-colour fish appear to have normal colour cells on the lower part of the body and imperfect ones on top,” states Jónbjörn Pálsson’s text when we asked about oddly-coloured redfish. Although the black redfish found at Nordurgardur has not been examined in detail by the Marine Research Institute, it can be assumed that all of its colour cells are imperfect.